On 11/04/2022 12.07, Nico Boehr wrote:
Add a basic implementation for reading from the SCLP ACII console. The goal of
s/ACII/ASCII/
this is to support migration tests on s390x. To know when the migration has been
finished, we need to listen for a newline on our console.
Hence, this implementation is focused on the SCLP ASCII console of QEMU and
currently won't work under e.g. LPAR.
Signed-off-by: Nico Boehr <nrb@xxxxxxxxxxxxx>
---
lib/s390x/sclp-console.c | 81 +++++++++++++++++++++++++++++++++++++---
lib/s390x/sclp.h | 7 ++++
s390x/Makefile | 1 +
3 files changed, 83 insertions(+), 6 deletions(-)
diff --git a/lib/s390x/sclp-console.c b/lib/s390x/sclp-console.c
index fa36a6a42381..8e22660bf25d 100644
--- a/lib/s390x/sclp-console.c
+++ b/lib/s390x/sclp-console.c
@@ -89,6 +89,10 @@ static char lm_buff[120];
static unsigned char lm_buff_off;
static struct spinlock lm_buff_lock;
+static char read_buf[4096];
+static int read_index = sizeof(read_buf) - 1;
+static int read_buf_end = 0;
+
static void sclp_print_ascii(const char *str)
{
int len = strlen(str);
@@ -185,7 +189,7 @@ static void sclp_print_lm(const char *str)
* indicating which messages the control program (we) want(s) to
* send/receive.
*/
-static void sclp_set_write_mask(void)
+static void sclp_write_event_mask(int receive_mask, int send_mask)
{
WriteEventMask *sccb = (void *)_sccb;
@@ -195,18 +199,27 @@ static void sclp_set_write_mask(void)
sccb->h.function_code = SCLP_FC_NORMAL_WRITE;
sccb->mask_length = sizeof(sccb_mask_t);
- /* For now we don't process sclp input. */
- sccb->cp_receive_mask = 0;
- /* We send ASCII and line mode. */
- sccb->cp_send_mask = SCLP_EVENT_MASK_MSG_ASCII | SCLP_EVENT_MASK_MSG;
+ sccb->cp_receive_mask = receive_mask;
+ sccb->cp_send_mask = send_mask;
sclp_service_call(SCLP_CMD_WRITE_EVENT_MASK, sccb);
assert(sccb->h.response_code == SCLP_RC_NORMAL_COMPLETION);
}
+static void sclp_console_enable_read(void)
+{
+ sclp_write_event_mask(SCLP_EVENT_MASK_MSG_ASCII, SCLP_EVENT_MASK_MSG_ASCII | SCLP_EVENT_MASK_MSG);
+}
+
+static void sclp_console_disable_read(void)
+{
+ sclp_write_event_mask(0, SCLP_EVENT_MASK_MSG_ASCII | SCLP_EVENT_MASK_MSG);
+}
+
void sclp_console_setup(void)
{
- sclp_set_write_mask();
+ /* We send ASCII and line mode. */
+ sclp_write_event_mask(0, SCLP_EVENT_MASK_MSG_ASCII | SCLP_EVENT_MASK_MSG);
}
void sclp_print(const char *str)
@@ -227,3 +240,59 @@ void sclp_print(const char *str)
sclp_print_ascii(str);
sclp_print_lm(str);
}
+
+#define SCLP_EVENT_ASCII_DATA_STREAM_FOLLOWS 0
+
+static int console_refill_read_buffer(void)
+{
+ const int MAX_EVENT_BUFFER_LEN = SCCB_SIZE - offsetof(ReadEventDataAsciiConsole, ebh);
+ ReadEventDataAsciiConsole *sccb = (void *)_sccb;
+ const int EVENT_BUFFER_ASCII_RECV_HEADER_LEN = sizeof(sccb->ebh) + sizeof(sccb->type);
+ int ret = -1;
+
+ sclp_console_enable_read();
+
+ sclp_mark_busy();
+ memset(sccb, 0, 4096);
+ sccb->h.length = PAGE_SIZE;
+ sccb->h.function_code = SCLP_UNCONDITIONAL_READ;
+ sccb->h.control_mask[2] = 0x80;
Add at least a comment about what the 0x80 means, please?
+
+ sclp_service_call(SCLP_CMD_READ_EVENT_DATA, sccb);
+
+ if ((sccb->h.response_code == SCLP_RC_NO_EVENT_BUFFERS_STORED) ||
+ (sccb->ebh.type != SCLP_EVENT_ASCII_CONSOLE_DATA) ||
+ (sccb->type != SCLP_EVENT_ASCII_DATA_STREAM_FOLLOWS)) {
+ ret = -1;
+ goto out;
+ }
+
+ assert(sccb->ebh.length <= MAX_EVENT_BUFFER_LEN);
+ assert(sccb->ebh.length > EVENT_BUFFER_ASCII_RECV_HEADER_LEN);
+
+ read_buf_end = sccb->ebh.length - EVENT_BUFFER_ASCII_RECV_HEADER_LEN;
+
+ assert(read_buf_end <= sizeof(read_buf));
+ memcpy(read_buf, sccb->data, read_buf_end);
+
+ read_index = 0;
Set "ret = 0" here?
+out:
+ sclp_console_disable_read();
+
+ return ret;
+}
+
+int __getchar(void)
+{
+ int ret;
+
+ if (read_index >= read_buf_end) {
+ ret = console_refill_read_buffer();
+ if (ret < 0) {
+ return ret;
+ }
+ }
+
+ return read_buf[read_index++];
+}
Thomas
